To prepare the prawns, remove the shells and heads (if there are any) but leave the tails on as they look very attractive. Then use the tip of a small sharp knife to cut a slit all along the back of each prawn and remove the black thread that sometimes runs from head to tail. Then place the prawns and capers in the dish together with the sliced peppers, onion and lemon.

Now in a bowl or jar whisk the oil, mustard, vinegar, lime juice, Worcestershire sauce and Tabasco together, adding the salt, a little coarsely ground black pepper and the sugar, then pour this mixture all over the prawns. Cover the container and place it in the fridge for at least 48 hours, giving the contents a shake or stirring them around from time to time.

Serve the prawns garnished with sprigs of coriander and slices of lime with plenty of the marinade poured over and lots of bread to mop up the juices.